Many types of input devices are available for performing operations in a computing system, such as buttons or keys, mice, trackballs, joysticks, touch sensor panels, touch screens, and the like. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface, and a display device such as a liquid crystal display (LCD) that can be positioned partially or fully behind the panel so that the touch-sensitive surface can cover at least a portion of the viewable area of the display device. Touch screens generally allow a user to perform various functions by touching (e.g., physical contact or near-field proximity) the touch sensor panel using a finger, stylus or other object at a location often dictated by a user interface (UI) being displayed by the display device.
Example touch screen input can include a drag gesture, wherein a user touches a user interface object and “drags” across the surface of the touch screen. A drag gesture can cause some manipulation of the user interface object based on the distance, velocity, or acceleration of the drag. Possible manipulations can include moving the user interface object or resizing the user interface object, for example. However, the number of manipulations possible with a simple drag gesture may be limited.